When you think about military and tool watches, oftentimes you will notice that the cases have been coated with something. It generally has a sandy or grainy texture or it has a black color, and sometimes it subtly changes the color of the material of the case, the latter being made of stainless steel or titanium. (For the most part.) These coatings were added for a specific reason and they differ in the way they look and sometimes in the way they are applied. In this non-scientific article, we will take a look at a few of these coatings—the most common ones in fact—and explain what they were created to do.
PVD Coating on Watches
Perhaps the most popular of all types of coating is PVD which stands for Physical Vapor Deposition. Although PVD refers to a process, typically PVD coating is made of titanium particles that are vaporized and fused onto the case to add protection against shock, scratches and scuffs. Titanium is an ultra resistant and light material that is often used to make watch cases, but sometimes brands prefer to do PVD instead of making titanium cases. Why? I’m not sure. But it works. PVD coating is easy to spot on a watch as it leaves a thin sandy texture on the case. One good example is the Hamilton Khaki Field Mechanical which case has been PVD coated.
DLC Coating on Watches
DLC, Diamond-like Coating, is a process by which carbon is applied to the case of a watch to make it super resistant to shocks. In order to make DLC cases, one must use the same process to make titanium-coated cases, in other words PVD. Particles of carbon are fused with the case in a vacuum chamber into a very thin layer onto the case. DLC is mostly used for extreme tool or sports watches as it has a resistance to scratch and shock that is far superior to that of naked stainless steel. The unique deep black appearance of DLC coated cases give these watches a stealthy appearance.
Cerakote Coating on Watches
The third type of popular coating is called cerakote. What it is, in a nutshell, is a very thin layer of ceramic applied to the case of the watch. Like titanium PVD coatings, it adorns the cases with a sandy texture that looks matte and very utilitarian. While it protects the watches from shocks and scratches, the additional feature of cerakote is that it protects against the elements, chemicals, and the harshest of climatic conditions. For these reasons, cerakote is often used on military equipment, although nowadays we also see it applied on watches.
Galvanization Coating on Watches
Last but not least, one type of protective treatment some brands put their watches through is called galvanization. Through this process, the watch case is coated with molten zinc or iron during the case manufacturing process in order to protect the steel from corrosion. It seems that galvanized cases are more common than I initially thought as it is a process that has been around for quite a while in the horological world. At least, that is my understanding. Galvanizing a watch case does not add the typical sandy texture of titanium-coating, but instead adds a subtle darker tone to the stainless steel.
Other Watch Proprietary Coatings
Although I do not know any of the specifics of it—because brands are protective of their own processes—more and more independent and micro-brands started adding what they describe as being a proprietary coating on watch cases and bracelets to protect them against scratches and corrosion. What I can tell you is that these mysterious coatings add a darker shade to the material used to make the case or bracelet, whether it be stainless steel or titanium. A bit like galvanization.
Watch brands have been working on ways to make watches and certain of their parts more resistant to scratches, shocks, and corrosion for many decades. You know the blue hands on your favorite pilot’s watch? Well, they have been heat-treated with a chemical to resist corrosion and tarnish. Have you heard of rhodium-plated hands, for example found on all MONTA watches? Well, rhodium is a transparent compound that protects the hands from corrosion and tarnishing.
In this article, we talked about case coatings and their purposes, and regardless of which process a brand has used, they have made their watches more resistant to daily wearing accidents and general wear. Perhaps in a future article I will talk about hand treatments and what makes them important.
Featured Image: www.theslenderwrist.com